1,239 research outputs found
Radiological evaluation of building materials used in Malumfashi, Katsina state, using gamma-ray spectroscopy analysis
The activity concentrations of naturally occurring radionuclides (226Ra, 232Th and 40K) in building materials (sand, cement, blocks, granite, and paints) used in the construction of buildings in Malumfashi local Government area of Katsina state, Nigeria were determined by means of a gamma-ray spectrometry system using Sodium Iodide thallium activated (NaI(Tl)) detector in a low background configuration. The average activity concentrations for 226Ra, 232Th and 40K ranged from 17.07±4.98 to 50.72±6.74, 23.03±1.54 to 42.91±2.37 and 84.03±5.44 to 363.45±5.27 Bqkg-1 respectively. Except for block samples, all the samples mean activity concentrations were less than their respective world averages. The estimated absorbed gamma dose rate (D) ranged from 30.75±4.22 to 64.57±4.78 nGyh-1and the outdoor annual effective dose equivalent (AEDE) varied from 0.038±0.004 to 0.06±0.0051 mSvy-1; these values are below the worldwide effective dose of 0.07 mSvy-1. The values of radium equivalent activity (Raeq), the external hazard index (Hex) and the internal hazard index (Hin) for all the samples in the present work were lower than the accepted safety limit value of 370 Bqkg-1.Keywords: Radionuclide, hazard indices, gamma-ray spectrometry, building materials, Malumfash
Predicting the minimum liquid surface tension activity of pseudomonads expressing biosurfactants
Bacteria produce a variety of biosurfactants capable of significantly reducing liquid (aqueous) surface tension (Îł) with a range of biological roles and biotechnological uses. In order to determine the lowest achievable surface tension (ÎłMin), we tested a diverse collection of Pseudomonas-like isolates from contaminated soil and activated sludge, and identified those expressing biosurfactants by drop-collapse assay. Liquid surface tension reducing ability was quantitatively determined by tensiometry, with 57 isolates found to significantly lower culture supernatant surface tensions to 24.5 â 49.1 mN mâ1. Differences in biosurfactant behaviour determined by foaming, emulsion and oil-displacement assays, was also observed amongst isolates producing surface tensions of 25 â 27 mN mâ1, suggesting that a range of structurally-diverse biosurfactants were being expressed. Individual distribution identification (IDI) analysis was used to identify the theoretical probability distribution that best fitted the surface tension data, which predicted a ÎłMin of 24.24 mN mâ1. This was in agreement with predictions based on earlier work of published mixedâbacterial spp. data, suggesting a fundamental limit to the ability of bacterial biosurfactants to reduce surface tensions in aqueous systems. This implies a biological restriction on the synthesis and export of these agents or a physical-chemical restriction on their functioning once produced
Efektivitas "Cognitive Behavior Therapy" Terhadap Penurunan Derajat Stres
Cognitive Behavior Therapy (CBT) is an effective way to decrease the degree of stress in patients with chronic Low Back Pain (LBP). Chronic LBP can be divided to physical and psychogenical view. Psychogenical LBP was result of cognitive process associated with stress. This study is conducted to get an idea of how the effects of CBT can help reducing the degree of stress in patients with chronic LBP in hospital 'X' Bandung.According to the results of this study, it can be concluded that Cognitive Behavior Therapy (CBT) is empirically proven to give effect on reducing the degree of stress in both chronic LBP patients in hospital 'X' Bandun
Assessment of Reliability and Availability of Series-Parallel Sub-Systems
The paper presents the explicit expressions for measuring reliability parameter of systems, Graphs were plotted to highlight important results. Results have shown that measures of system effectiveness such MTSF, system availability and profit increases with repair rates and decreases with failure rates.The developed model helps in determining the optimal maintenance strategies which ensure the maximum overall availability of the system. The optimum values of failure and repair rates for each subsystem were given. It is observed that the first subsystem is having the maximum availability with (97%). The optimum values of failure and repair rates for maximum availability level for each subsystem is also shown. Keywords: Mean time to system failure, Availability, Reliability, Maintenance and Subsystem
Impact of export incentive schemes on the performance of agricultural exports in Nigeria
Abstract. This paper examines the impact of export incentive schemes on the Performance of agricultural exports in Nigeria, using quarterly time series data from 1990-2014. The study employed Autoregressive Distributed Lag (ARDL) model to cointegration analysis and Granger causality test to examine the long run and causality relationship between growth in the Performance of agricultural exports and export incentive schemes in Nigeria. The bounds tests used in the study revealed that there is no long run equilibrium relationship between export incentive schemes and the performance of agricultural exports in Nigeria. It is of high importance to note that the granger casualty test indicates that there was a unidirectional relationship running from agricultural export (AGR) to export expansion grant (EEG), export development fund (EDF) to agricultural export (AGR). Since the findings of the study show that export development fund has positive and significant impact on the performance of agricultural exports in Nigeria, the study suggests that major concern should be given to its management and disbursement to ensure stable growth in the sub-component (agriculture) of non-oil export in Nigeria. This can be achieved through adequate funding by the concerned authority.Keywords. Export incentives, Non-oil exports, Causality, ARDL, Nigeria. JEL. J43, Q00, Q10
Growth performance, carcass and organ characteristics of growing rabbits fed graded levels of Moringa oleifera leaf meal in diets
An experiment was conducted at the Department of Animal Science teaching and research farm, Bayero University Kano, to evaluate the effect of feeding graded levels of Moringa oleifera leaf meal (MOLM) in diets on growth performance, carcass and organ characteristics of weaned rabbits. Twenty eight grower rabbits of averagely 975g in weight were allotted into four treatments of seven rabbits each in a completely randomize design. Four isonitrogenous diets (16% CP) were formulated in which MOLM was included at 0, 15, 30 and 45% for treatments 1, 2, 3 and 4 respectively. The diets were fed to the animals for eight weeks. The result showed that daily weight gain (5.95-13.39g/day) and carcass weight (497.70-727.65g) increased (P<0.05) with increasing levels of MOLM in diets, but dressing percentage (42.49-45.96%) was not affected by dietary treatments. Similarly, the weight of liver (40.35-57.05g), lungs (10.22-11.24g), heart (2.95-4.10g), kidney (8.30-10.70g), kidney fat (11.10-12.65g), small intestine (81.25-99.80g), large intestine (102.45-117.95g), caecum (20.50- 30.50g), stomach (90.75-114.65g), spleen (1.00-1.80g) and abdominal fat (7.89-11.25g) characteristics were not different across the treatments. The results indicate that weaned rabbits can utilize Moringa oleifera leaf meal at up to 45% level of inclusion in diets without any deleterious effects on growth performance, carcass yield and organ characteristics.Key words: Carcass yield, growth, Moringa oleifera, organ characteristics, rabbit
Sebaran Muatan Padatan Tersuspensi Dan Kelimpahan Fitoplankton Di Perairan Muara Sungai Porong Kabupaten Sidoarjo
Pembuangan limbah dan lumpur ke Sungai Porong diduga akan berdampak bagi lingkungan sekitarnya, khususnya meningkatnya konsentrasi Muatan Padatan Tersuspensi (MPT) dan mempengaruhi sebaran fitoplankton di wilayah tersebut. Tujuan dari dilakukannya penelitian ini adalah untuk mengetahui konsentrasi muatan padatan tersuspensi, kekeruhan dan kelimpahan fitoplankton di perairan muara Sungai Porong, Kabupaten Sidoarjo. Metode penelitian yang digunakan adalah metode deskriptif. Data yang dikumpulkan sebagai variable ukur adalah muatan padatan tersuspensi, kekeruhan, kelimpahan fitoplankton dan kecepatan serta arah arus. Variabel pendukung meliputi data arah dan kecepatan arus dan peta bathimetri wilayah muara Sungai Porong. Data yang diperoleh selanjutnya dianalisis menggunakan program Arc GIS 10, sehingga menghasilkan output berupa distribusi spasial. Konsentrasi muatan padatan tersuspensi 542-885 mg/l. konsentrasi kekeruhan 3.7-20.5 NTU. Kelimpahan fitoplankton 153-238 ind/l. Berdasarkan data tersebut dapat diketahui bahwa sebaran muatan padatan tersuspensi dan kekeruhan memiliki kaitan dengan kelimpahan fitoplankton pada saat surut, meskipun pada kuantitas yang tidak selalu sama. Arah sebaran bergerak ke arah Timur atau menjauhi muara sungai
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